diff --git a/src/proto_http.c b/src/proto_http.c
index 48cb383a0..39900deac 100644
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -7566,8 +7566,10 @@ void http_end_txn(struct stream *s)
 		memset(s->res_cap, 0, fe->nb_rsp_cap * sizeof(void *));
 	}
 
-	vars_prune(&s->vars_txn, s->sess, s);
-	vars_prune(&s->vars_reqres, s->sess, s);
+	if (!LIST_ISEMPTY(&s->vars_txn.head))
+		vars_prune(&s->vars_txn, s->sess, s);
+	if (!LIST_ISEMPTY(&s->vars_reqres.head))
+		vars_prune(&s->vars_reqres, s->sess, s);
 }
 
 /* to be used at the end of a transaction to prepare a new one */
diff --git a/src/stream.c b/src/stream.c
index ad1ccbee4..d27dae3a2 100644
--- a/src/stream.c
+++ b/src/stream.c
@@ -376,8 +376,10 @@ static void stream_free(struct stream *s)
 	}
 
 	/* Cleanup all variable contexts. */
-	vars_prune(&s->vars_txn, s->sess, s);
-	vars_prune(&s->vars_reqres, s->sess, s);
+	if (!LIST_ISEMPTY(&s->vars_txn.head))
+		vars_prune(&s->vars_txn, s->sess, s);
+	if (!LIST_ISEMPTY(&s->vars_reqres.head))
+		vars_prune(&s->vars_reqres, s->sess, s);
 
 	stream_store_counters(s);
 
@@ -2258,8 +2260,10 @@ redo:
 
 		/* prune the request variables and swap to the response variables. */
 		if (s->vars_reqres.scope != SCOPE_RES) {
-			vars_prune(&s->vars_reqres, s->sess, s);
-			vars_init(&s->vars_reqres, SCOPE_RES);
+			if (!LIST_ISEMPTY(&s->vars_reqres.head)) {
+				vars_prune(&s->vars_reqres, s->sess, s);
+				vars_init(&s->vars_reqres, SCOPE_RES);
+			}
 		}
 
 		do {